Roll stock cradle structure

ABSTRACT

Roll stock cradle support structure for receiving and supporting one or more pieces of roll stock, comprising: a flat base strip of rigid or semi-rigid plastic material having an upper and lower surface, at least one set of facing cradle portions of pre-selected dimensions integrally formed on one base strip surface, forming a roll support cradle, said cradle portions comprising a substantially vertical end wall and an arcuately shaped segment of rigid or semi-rigid plastic material, said segment being reinforced by members connecting the arcuately shaped segments with the end wall or base strip.

This application is a filing under 35 USC 371 of PCT/IL2003/000730 filedSep. 4, 2003.

FIELD OF THE INVENTION

The present invention relates to a roll stock cradle support structurefor supporting horizontally lying cylinders, such as roll stock and thelike, that allows their stacking, and to stacking systems incorporatingsuch supporting cradles.

BACKGROUND OF THE INVENTION

There is frequently a need for storing and transporting round elongatedobjects, such gas cylinders, drums, and particularly ‘rollstock’—cylindrical rolls of thin materials such as fabrics, polymerfilms, nets, paper products, aluminium foils and the like. Typically,roll stock is shipped and stored on pallets in horizontally orientedtiers. To stabilize and support these rolls in their tiers, stackingsupport structures are employed.

Typically, such support structures are made from cheap wood. Where heavyroll stock is transported using such wooden stacking supports, it hasbeen found that such supports are subject to breakage during lifting andtransportation, with an inherent risk of damage to the roll stock.Wooden roll supports have a tendency of splinter, and haulers are atrisk from injury. Furthermore, wooden roll supports are not flexible andcannot accommodate rolls of varying diameters. Moreover, they are bulky,wasteful of natural resources, and are not cheap to manufacture. Woodensupports must also be protected from the elements, and, in manyinstances require treating the wood with pesticides, which of course,increases the unit cost. These supports cannot be stored outdoors in wetweather, since the wood will rot or warp.

Thus there has been a constant desire to replace wooden stackingsupports, and numerous patents address this problem. U.S. Pat. No.4,195,732 to Bell, and U.S. Pat. No. 4,832,196 to Butler, for example,both describe roll support members formed of expanded polystyrene foam.Expanded polystyrene is lightweight and does not produce splinters.However, there are other problems associated with expanded polystyreneroll stock supports, such as their brittleness and poor strength as wellas their bulkiness. These supports are easily broken and take upsignificant storage space when unused.

In an apparent attempt to improve upon the inadequacies of polystyrenefoam, U.S. Pat. No. 5,080,314 to Moyer, discloses a roll supportstructure formed from recyclable papier-mache. Although less brittlethan expanded polystyrene and easier to dispose of, since papier-machedisintegrates when wet, such supports cannot be used in humidenvironments and always must be protected from weather, which isespecially difficult while transporting, unless in closed containers.Papier-mache supports must also be fabricated with substantial thicknessto support heavy roll stock, and therefore, they are bulky and require alot of storage space indoors.

U.S. Pat. No. 6,209,839 to O'Malley, describes nestable cradle supportsfor stacking roll stock fabricated from polyethylene terephthalate(PET). Such supports are both compact and easily fabricable, and byvirtue of their stackability, they are easily transportable. PET is alsoresistant to the elements allowing these supports to be stored outdoors.The supports described are fabricated as double strips, which may befolded lengthwise. The double strips are used as base supports for afirst tier of roll stock and the folded strips for further stackingadditional rolls on top of the first tier. The roll stock supportsdisclosed in this patent, however, have several disadvantages. First ofall, PET is not a particularly cheap feedstock polymer. Secondly, thecradles of the support structures are resistant to deformation and eachcradle within the support must be sized for the particular roll diameterto be stacked. Such a rigid structure is advantageous for stackingidentical rolls such as rolls of fabric, paper or certain films.However, the lack of flexibility of the support structure prevents goodstacking of rolls of non-uniform diameter, and adversely affects thestability of the stack thus formed. Furthermore, pallets with stackedroll stocks placed on these supports must generally be banded to keepthe rolls from falling out of the stack. Thus, there is still a need foran inexpensive flexible cradle support structure for stacking rollstock, that is weather resistant, recyclable and suitable for stackingrolls with somewhat varying diameters. The present invention is directedto providing such a support.

DE 19908621A discloses rigidly connected cradle supports. The cradlescan be come in sections that can be attached to each other.

EP 0706949A1 discloses triangular elastic wedges as supports for loadson palles.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a cradle supportstructure for stacking cylindrical structures such as roll stock, inhorizontal tiers.

It is a further object of the present invention to provide a cradlesupport structure that can accommodate rolls of somewhat varyingdiameters, yet allow them to be stably stacked, without requiringbanding.

A still further object of the present invention to provide a cradlesupport structure that lends itself to mass production, is cheap tomanufacture, long-lasting and recyclable.

Another object of the present invention to provide a cradle supportstructure that may be fabricated from recycled polymer feedstock.

Yet another object of the present invention to provide a cradle supportstructure that may be easily affixed to a wooden pallet to provide aconvenient base support for the bottom tier of a roll stock.

Still another object of the invention is to provide a method ofmanufacturing cradle support structures in accordance with theinvention.

According to the present invention there is provided a roll stock cradlesupport structure for receiving and supporting one or more pieces ofroll stock, comprising:

a flat base strip of rigid or semi-rigid plastic material having anupper and lower surface,

at least one set of facing cradle portions of pre-selected dimensionsintegrally formed on one base strip surface, forming a roll supportcradle,

said cradle portions comprising a substantially vertical end wall and anarcuately shaped segments of rigid or semi-rigid plastic material, saidsegment being reinforced by members connecting the arcuately shapedsegments with the end wall or base strip.

The cradle support structures have at least two or more support cradles,each comprising terminal cradle portions at the ends of the base stripand back to back cradle portions having their arcuate segments facingaway from each other positioned between the terminal cradle portions.Preferably, the central back to back cradle portions are spaced apartwith deformable plastic connecting segments. These deformable plasticconnecting segments are preferably curved strips whose curvature isdeformable under pressure. Generally, each cradle support structure willhave between two and 10 support cradles.

The roll stock cradle support structure may have support cradles on oneor both surfaces of the base strip and is preferably manufactured frompolyolefin polymers, for example, polyethylene, polypropylene, andmixtures or copolymers of these. Most preferably the support structuresare manufactured from recycled polymers, which is advantageous from anecological point of view, and they are also cheaper. The dimensions ofthe cradles are such that the vertical height of the cradle is between100 and 1000 mm, the width between 10 and 300 mm, and the arcuatelyshaped segments of the cradles have arc diameters of between 200 and 320mm.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be further understood and appreciated fromthe following detailed description taken in conjunction with thedrawings in which:

FIG. 1 is a perspective view of a stack or roll stock with cradlesupport structures in accordance with this invention,

FIG. 2 is a blown up front view of the stacked roll stock of FIG. 1,

FIG. 3 is a side view of a cradle support structure having cradles ononly one surface of the structure,

FIG. 4 is a top view of the cradle support structure of FIG. 3,

FIG. 5 is a side view of a cradle support structure having cradles onboth surfaces of the structure,

FIG. 6 illustrates another embodiment of a double sided cradle supportstructure in accordance with the invention,

FIG. 7 is still another embodiment of a double sided cradle supportstructure according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIGS. 1 and 2, there is shown a multi-tiered stack 10of rolls stacked on a pallet 14. The pallet 14 has affixed to its bottoma single-sided cradle support structure 16 onto which is placed a firstrow 18 of roll stock. Above this row 18 of roll stock is placed adouble-sided support structure 20. Further alternating rows of rolls 22,26, 30, etc. and double-sided support structures, 24, 28 etc. are added,thus forming a multi-tiered stack 10 of rolls. The stack is stable andwill not topple, yet does not require banding.

FIGS. 3 to 5 illustrate one embodiment of the present invention. FIG. 3shows a single-sided cylindrical support structure 16 consisting of asubstantially flat base strip 32 which has integrally formed thereonleft 34 and right 36 cradle end portions and complimentary center cradleportions 38 and 39 respectively. The cradle portions 34 and 38, and 36and 39 have substantially vertical end walls 41 and arcuate shapedsegments 40 and 42, and 44 and 46 facing each other, respectively, thusforming between them a cradle support.

Tangential reinforcing members 48 connect the arcuate segment 40 to itsend walls 41, whereas reinforcing members 50 and 52 connect the arcuatesegments with the base strip 32. The center cradle portions 38, 39 areslightly spaced apart 62 and are connected at their vertical ends by acurved strip of plastic 64 which is deformable when a heavy load isplaced on the cradle, thereby making the arc of the cradle adjustable tothe diameter and weight of the roll stock. The height of the end walls41 of the cradle segments can range from 3 to 10 cm, preferably from 40to 60 mm. The diameter 60 of the cradle is preferably in the range of200 to 320 mm.

FIG. 5 illustrates a roll stock cradle 54, basically the same as in FIG.3 with the exception that it also has cradle supports 56, 58 on theother side of the flat base strip 32.

The exact configuration of the single and the double-sided cylindricalsupport structures of the present invention can be adapted to particularapplications, and loads, and several alternative configurations areillustrated in FIGS. 6 and 7.

The cylinder support structures of the present invention have severaladvantages over those of the prior art, notably the design of the cradlesupports 56, 58 provides a flexibility that enables them to stack rollsof varying diameter safely, since the base strip is flexible and eachcradle support operates independently. Several tiers of rolls can bethus stacked by alternating layers of rolls between double sidedsupports. Such stacked tiers are sturdy and do not generally requirebanding. The roll stock cradle supports may be used for stacking rollsof different lengths, diameters and weights.

The roll stock cradle supports of this invention are best manufacturedby thermoforming, more specifically by injection molding. This producesa very satisfactory product with low production cost. Moreover, thismethod allows the use of recycled polymer, and the product can even berecycled further.

The thermoformed roll stock polymeric cradle support describedhereinabove is tough and resistant to mishandling, stable in extremes ofhot and cold, and resistant to moisture. By incorporating carbon blackas a filler, for example, the plastic used may be made UV resistant andmay be exposed to sunlight for many years. Unlike wooden or expandedpolystyrene cradle supports, there is little danger of splintering orfragmenting.

It will be noted that when preparing a pallet for loading thereon rollstock, first the flat base strip of one sided roll stock cradle supportsis fixed to the palate, using nails or staples for example, to provide abase layer for stacking a first row of roll stock. The roll stock isthen arranged in parallel in the cradle supports and a double sidedcradle support is placed on top of the rolls, and so on.

It is to be understood that the exact dimensions and shape of thedifferent parts of the support structure may vary depending on thediameter, weight and length of the roll stock to be supported. Theexamples shown herein are for purposes of illustration only.

1. Roll stock cradle support structure for receiving and supporting oneor more pieces of roll stock, comprising: a flat flexible base strip ofrigid or semi-rigid plastic material having a longitudinal axis and anupper surface and a lower surface, at least one set of facing cradleportions of pre-selected dimensions integrally formed on top of andalong the longitudinal axis of one flat base strip surface in a singlerow, with a section of flat base strip surface separating the facingcradle portions, thereby forming a roll support cradle, each cradleportion comprising a substantially vertical end wall and an arcuatelyshaped segment of rigid or semi-rigid plastic material, said segmentbeing reinforced by members connecting the arcuately shaped segmentswith the end wall or base strip, said structure providing a flexibilitydue to the independent operation of the cradle portions and due to theflat plastic base strip between the cradle portions, allowing for rollstock of varying diameter sizes to be stacked securely.
 2. A roll stockcradle support structure as in claim 1, having at least two supportcradles formed on the one flat base strip surface, each structurecomprising cradle portions which are terminal cradle portions at theends of the base strip and at least one pair of back to back cradleportions having arcuate segments facing away from each other positionedbetween the terminal cradle portions, the facing cradle portionsseparated by a section of the flat base strip, said structure providinga flexibility due to the independent operation of each support cradleand the flat plastic base strip, allowing for stock of varying sizes tobe stacked securely.
 3. A roll stock cradle support structure as inclaim 2, wherein the central back to back cradle portions are spacedapart with deformable plastic connecting segments.
 4. A roll stockcradle support structure as in claim 3 wherein the deformable plasticconnecting segments are curved strips whose curvature is deformableunder pressure.
 5. A roll stock cradle support structure as in claim 2,having between two and 10 support cradles.
 6. A roll stock cradlesupport structure as in claim 1, having support cradles on both surfacesof the base strip with flat base strip sections separating facing cradleportions, and with cradle portions on the upper surface and cradleportions on the lower surface in opposed relationship.
 7. A roll stockcradle support structure as in claim 1, wherein the plastic material isa polyolefin polymer.
 8. A roll stock cradle support structure as inclaim 7 wherein the plastic material is selected from the groupconsisting of polyethylene, polypropylene, mixtures or copolymers ofpolyethylene and polypropylene and recycled products of polyethylene andpolypropylene.
 9. A roll stock cradle support structure as in claim 1,wherein the arcuately shaped segment has an arc diameter of between 200and 320 mm, and the vertical height of the cradle is between 100 and1000 mm.
 10. A method of manufacturing roll stock cradle supportstructures as claimed in claim 1 comprising providing a suitable moldand injection molding therein a thermoplastic polymer at predeterminedtemperature, cooling the mold and removing the support structuretherefrom.